Method of extracting sugar from sugar beets



Oct. 19, 1943. R CUTLER 2,332,062

METHOD OF EXTRACTING SUGAR FROM SUGAR BEETS Filed Feb. 12, 1941 H GRINDER I 0| CRUSHERS/I as SEPARATOR PRESS HOT JUICES us SEPARATOR 1 I HOT WATER PRESS SEPARATOR DRYER SILO gunmen/tom ThomusR.Curler Patented Oct. 19, 1943 STATES: BAT OFFICE METHOD OF EXTBAGTING' SUGAREROM SUGARBEETS w T meless. Cutler, Idaho Falls, Idaho Application February 12, 1941,. Serial No; 378,691"

3 Claims: (011127 4 3) My invention relates to :a method of treating sugar beets for extracting the sugar therefrom.

Important-objects 'ofgtheinvention are to reduce the time in which the juice containing the sugar may be extracted:fromxthezbeet, from 30 to e5yminutes; tozreduce 'the' draft -,or quantity of-waternow employed'fronr 30%.to. 60%; to increaseithecapacity ofithe factory, by reducing the'quantity, of water and. increasing, the quality of -thejuice; ,to reduce coal consumption; to reduce labor "costs; tomaintainhigher purities in the extracted-juices; toincrease eiiiciency by having abetter control of the density of the juice; to eliminateentirely the chance of less in sugar. which is the: constant. danger: with duifusionbatteries; to reduce'the; quantity of steam or vapors, byn-ot heating all the pulp or mash; to reduce the quantityof water as compared with that necessary, for operating difiusicn batteries.

Other objects-and advantages of'the invention will be apparent during-the courseof the follow-' ness of the process serving-itcretard, any tend;

ency; of r the sugar content becoming inverted, The extractedI-juicesfromthe-press 2 are con veyed to. atank 3, and the temperature. of the juices within this tank is maintained at at least 85, C. to 90 'C.. 'I'-he.-juices are: extracted by pressure from the iine even, mash having; the sugar cells ;of l the beets disrupted, immediately afterFthe-grinding operatiom and without anyv added water, andthisz has been found to prevent certain impuritiesimmbeingcontained: within the juices. The maximum amount of juices will thusbeseparatedtout from. the beet mash, and the 3 amount; of juices; will vary to some 1 extent; but the juices-extracted should amount to from 30% to.40 ;by Weightwith' respect to the weight of'the-beets. The extracted juiceswill show the total amount of sugar-per. cent and also the purityof'the-beets being; worked. The invention throughapparatusd, which may bera grinder or crusher. This grinding or crushing action disrupts .-the. sugar. cells of thebeets :and produces a fine even pulp. Thegrinding or crushing action isia' coldlprocess andis carried out at room temperature, without added water.

The next stepin the methodis to. subject the line even mash to-pressure tor the purpose of separating out the juices containing the sugar, and. the pressing step should follow immediately after the grinding step. The fine even'mashis introduced into a hydraulic press 2" and the juices squeezed from the=mash. The pressing step perature without addediwater; tracted by the pressing step must be free from fine'particlesof pulp, and may be strained or filtered for this purpose. The extracted juices containing the sugar, immediately after the pressing step, are heated to a temperature of at least 85 C. and these juices are maintained at at least 85 C. throughout the process, the quick- 'is acold process-as 'it-is'carried out atroom'tem- The juices eX-' 1811101, restricted 'to the: useof hydraulic presses, as "I maygusei at screen conveyor I with a series of rolls or other: appliances forextracting orpressingntheqjuicesirom :the pulp:

The-beet pulprhaving itscells disrupted and the major portion of its water content removed,

is-now removed-fromthe pressZ and ispassed to -thepress *4,- similar to press 2, through a ,conveyor 5; The several steps of the method should be substantially; continuous, and'as soon as the pulpn'has: its pressing operation completedin press 'lsit' should be discharged into the conveyor 7 5;. While. passing; through the conveyor 5 the beet pulp: or: mash :is: thoroughly agitated and has hotnwaterzor hot'juices .appliedithereto,"inithe presenceeoflagitation; The hotliquid appliedrto the'..mash'i1'or:: pulp in-.the; conveyor may consist of hot water orshgt juices or a mixtureof the same,'.and this.,hot liquor;- should be added in e from 40%: to by weightrwithrespectto the weight of :1 the mash,.and the; hot liquor should bemaintained:ataartemperature of at least C.

The beet: mash-:Etraveling in the conveyor isa spongymass onaccountiofthe:cells of the beets being disrupted and is i highly. absorbent and will practically instantaneously-absorb:the hot liquor 1 applied thereto, whiletthe mash is being agitated. The mash .thustieatedwith the added hot liquor isz immediatelyintroduced into the second press 4; and. therein immediately subjectedito pressure,

to separate out the juices. containingithe sugar,

As stated, the mash is highly absorbent, and I have discovered that the best results are obtained by allowing the juice to remain with the mash only long enough for the mash to be saturated. Therefore as soon as the mash is saturated it is immediately pressed to extract the juices. These juices discharge through a pipe 6 and are conducted to the tank 3, containing the previously extracted juices. The temperature of the juices passing through the pipe 6 should be maintained at at least 85 C. p

The mash is now immediately removed from the press I and passed through a conveyor 1 toward a third press 8. While passing through the conveyor 1 the mass is constantly agitated and is subjected to the action of hot water applied thereto. The water is preferably supplied at a temperature of 98 C. to 100 C. I preferably add from 40% to 60% by weight of waterwith respect to the weight of mash. The mash from the press! will rapidly absorb the added water, and as soon as thi mash is saturated it is pressed to extract the juices. The pulp containing the added water now therefore passes into the third press 8, as soon as it is saturated, and the juices are immediately pressed from th pulp as the best results are obtained by allowing the juice to remainwith the mash only long enough for the mash to, be saturated, and these juices pass through a pipe 9, which leads to'the conveyor 5, and this is the source of the hot juices for the conveyor 5. These hot juices contain somesugar. The temperatureof the juices discharging through the pipe 9 is maintained at a temperature of at least 85 C. The third juice from this press 8 will contain a small amount of sugar, and the solid matter in degree Brix will be 4% to 6% of the degree Brix in the first juice. The hot water in the conveyor 1 may beobtained by added steam or vapor and cold water.

The pulp isnow discharged from the press 8 and contains very little, if any, sugar and contains 80% to'85% of moisture and can be conveyed to a silo or dryer, as is well known in the art. All steps of the process from the time thatthe beets are introduced into the grinder I up to and through the time that the pulp is discharged from the press 8, are continuous and these steps may be completed within ten minutes. 1 1

The juices from the first press 2 which is 30% to 40% of the weight of the beet contain from 16% to 20% solid matter or degree Brix. The juices from the press 4 consist of the added hot water or hot juices which will absorb additional sugar from the mash after the first extraction, and these juices from the press 4 will contain from 8% to 12% solid matter or degree Brix. The juices from the third press 8 comprising the added hot water will absorb a small amount of sugar from the mash and will contain about 4% of solid matter or degree Brix.

The total amount of juices extracted from the three presses will be from 80% to 100% 'of the weight of the beets. The total weight of the juices being reduced, with respect to the prior art method, it will contain a higher per cent of solid matter or degree Brix. Sugar technologists in the beet sugar business have maintained that the breaking of the sugar cells of the beet would allow the impurities free access to pass out with the juice. This is believed to be true with the diffusion or osmatic action, because of the long period in which the cossetts or beet mash is held in the diffusion battery, where the whole mash is heated and the per cent of water entering is such that in many cases the per cent of juice drawn from the difiusion will run to 160% of the weight of the beets worked, in order to reduce the amount of sugar remaining in the pulp. With the diffusion or osmatic action, for many years,

the amount of sugar remaining in the pulp and pulp water would be .35% to .40% but in recent years this has been reduced from 20% to In accordance with my method it is possible to obtain a total of .05% without imparting detrimental impurities to the juice.

While I have described the juices as beingseparated from the pulp by a pressing action, this separation may be effected by other means.

The juice containing the sugar and held within the tank 3, are subjected to clarification, evaporation, and crystallization, to recover the sugar content in the solid form, as is well known. The juices are maintained at a temperature of at least 85 C. until the sugar is recovered in the solid form.

Having thus described my invention, what I claim is:

1. The method of extracting sugar from sugar beets, comprising finely dividing the sugar beets for producing a cold mash having the sugar cells of the beets disrupted, separating the juices from the cold mash, adding hot juices derived from a subsequent separation to the mash obtained from the first separation so that the mash is saturated, immediately separating the hot juices from the mash as soon as possible after the completion of the saturation of the mash, combining the second juices with the first juices, immediate- 1y subjecting the mash from the second separation to the action of hot Water so that the mash is again saturated, and separating the juices from the mash as soon as possible after the saturation, the last mentioned juices being supplied to the mash resulting from the first separation.

2. The method of extracting sugar from sugar beets comprising slicing and grinding cold beets to form a cold mash, straining juice from the mash, pressing out cold juice from the mash, heating the juice, saturating the mash and immediately pressing out juice therefrom, the last mentioned juice being mixed with the heated juice, again saturating the mash and immediately pressing juice therefrom, the last mentioned juice being heated and employed for saturating the mash prior to the second pressing.

3. The method of extracting sugar from sugar beets comprising reducing raw beets to a cold mash, subjecting the cold ,mash to a press to extract cold juice, said juice being delivered to a container, conveying the pressed mash to a second press and while in transit saturating the pulp with juice obtained during a subsequent pressing operation, juice from the second press being delivered into the container and mixed with the first juice, conveying the mash from the second press to a third press and during transfer to the third press saturating the mash with steam or hot water, and subjecting the saturated mash to action of the third press, hot juice from the third press being sprayed upon the mash in transit between the first press and the second press for saturating the same.

THOMAS E. CUTLER. 

